title: Inheritance profile of weathered chlordane and p,p'-DDTs accumulation by Cucurbita pepo hybrids.
abstract: Cucurbita pepo ssp pepo (zucchini) accumulates significant levels of persistent organic pollutants in its roots, followed by unexpectedly high contaminant translocation to the stems. Most other plant species, including the closely related C. pepo ssp ovifera (squash), do not have this ability. To investigate the mechanism of contaminant accumulation, two cultivars each of parental zucchini and squash, as well as previously created first filial (F1) hybrids and F1 backcrosses (BC) of those parental cultivars, were grown under field conditions in a soil contaminated with weathered chlordane (2.29 microg/g) and DDX residues (0.30 microg/g; sum of DDT, DDE, DDD). The parental zucchini had stem-to-soil bioconcentration factors (BCF, contaminant ratio of stem to soil) for chlordane and DDX of 6.23 and 3.10; these values were 2.2 and 3.7 times greater than the squash, respectively. Chlordane and DDX translocation factors, the ratio of contaminant content in the stems to that in the root, were 2.1 and 3.2 times greater for zucchini than for squash. The parental zucchini and squash also differed significantly in chlordane component ratios (relative amounts of trans-nonachlor [TN], cis-chlordane [CC], trans-chlordane [TC]) and enantiomer fractions for the chiral CC and TC. Hybridization of the parental squash and zucchini resulted in significant differences in contaminant uptake. For both the three separate component ratios (CR) and two sets of enantiomer fraction (EF) values, subspecies specific differences in the parental generation became statistically equivalent in the F1 hybrid zucchini and squash. When backcrossed (BC) with the original parental plants, the zucchini and squash F1 BC cultivars reverted to the statistically distinct CR and EF patterns. This pattern of trait segregation upon hybridization suggests either single gene or single locus control for persistent organic pollutant (POP) uptake ability by C. pepo ssp pepo.
authors.affiliation: Sakarya University, Department of Environmental Engineering, Esentepe Campus, Sakarya, Turkey. mehmet.isleyen@gmail.com
authors.forename: Mehmet
authors.initials: M
authors.lastname: Isleyen
authors.forename: Pinar
authors.initials: P
authors.lastname: Sevim
authors.forename: Joseph
authors.initials: J
authors.lastname: Hawthorne
authors.forename: William
authors.initials: W
authors.lastname: Berger
authors.forename: Jason C
authors.initials: JC
authors.lastname: White
mesh_terms: D001673:Biodegradation, Environmental; D018533:Biomass; D002678:Chimera; D002706:Chlordan / Q000032:analysis / Q000378:metabolism*; D003433:Crosses, Genetic; D028464:Cucurbita / Q000235:genetics / Q000378:metabolism*; D003634:DDT / Q000032:analysis / Q000378:metabolism*; D003633:Dichlorodiphenyl Dichloroethylene / Q000032:analysis / Q000378:metabolism*; D040582:Inheritance Patterns; D007306:Insecticides / Q000032:analysis / Q000378:metabolism*; D010573:Pesticide Residues / Q000032:analysis / Q000378:metabolism; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D018547:Plant Stems / Q000378:metabolism; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism; D013045:Species Specificity
chemical_list: D007306:Insecticides; D010573:Pesticide Residues; D012987:Soil; D012989:Soil Pollutants; D002706:Chlordan; D003633:Dichlorodiphenyl Dichloroethylene; D003634:DDT